A headrest support having a hollow cylindrical shape and into which a headrest stay is inserted, is inserted into a bracket that has a hollow cylindrical shape and is fixed to a seat back frame. A protrusion, a tip end of which is a pivot center of the headrest support, formed such that a protrusion amount thereof increases in response to insertion of the headrest stay, is provided on an outer peripheral surface of this headrest support.

The technology described in this document can be embodied in a headrest of a seat, the headrest including an enclosure for housing one or more acoustic transducers, and an adjustable headrest wing disposed in front of the enclosure. The headrest wing is coupled to the enclosure by a pivot, and configured to be adjusted to one of multiple positions within an angle range around the pivot. The headrest wing is also configured to support the head of a seat-occupant. The headrest further includes a connector disposed between the enclosure and a rear portion of the headrest wing. The connector is configured to provide an acoustic channel between the enclosure and the headrest wing such that audio signals from the one or more acoustic transducers are radiated outward through the headrest wing.

The technology described in this document can be embodied in a method for controlling acoustic output radiating through an adjustable wing of a seat headrest. The method includes receiving, from a sensor disposed in the seat headrest, an input signal indicative of a position of the adjustable wing. The position can be one of multiple positions within an angle range. The method also includes updating, based on the input signal, values for one or more control parameters associated with a transducer that generates the acoustic output radiating through the adjustable wing, and adjusting the transducer in accordance with the position of the adjustable wing using one or more control signals that are generated based on the updated values of the one or more control parameters.

A support rod for a vehicle seat head restraint, which is formed as a tube, having at least one structure as part of a locking device and intended for cooperating with a catch of the locking device which is associated with a holding structure. The structure has a base surface which prevents movement of the catch radially to a central axis of the support rod and includes a catch surface that prevents, together with the catch, movement of the support rod in a first direction. At least one catch structure as a detent structure has a cut-out tongue. An inner surface of the tongue radially facing a central axis of the support rod at a free end being spaced apart from the base surface by a height so that the catch is movable at least with a partial region radially under a region of the inner surface of the tongue.

A support rod for a vehicle seat head restraint, which is formed as a tube, having at least one structure as part of a locking device and intended for cooperating with a catch of the locking device which is associated with a holding structure. The structure has a base surface which prevents movement of the catch radially to a central axis of the support rod and includes a catch surface that prevents, together with the catch, movement of the support rod in a first direction. At least one catch structure as a detent structure has a cut-out tongue. An inner surface of the tongue radially facing a central axis of the support rod at a free end being spaced apart from the base surface by a height so that the catch is movable at least with a partial region radially under a region of the inner surface of the tongue.

A quickly installed headrest adjustment device includes a mount case connected to the chair back and includes a recessed area, an engaging hole, a latch and a first contact face on the rear side of the chair back. The engaging hole is located between the two side slots and defined through the inner bottom of the recessed area. The latch is connected to the inner top side of the engaging hole and includes a bottom face which protrudes beyond the engaging hole and faces the inner side of the recessed area. An adjustment device is mounted to the rail and includes a second contact face facing the first contact face, two ridges, and a block. The block is located between the two ridges. The users can connect the adjustment device to the mount case of the chair back to quickly install the headrest unit to the chair back.

A child restraint includes a seat bottom and a seat back. The seat back includes a backrest and an adjustable headrest that is mounted for up-and-down movement on the backrest by a caregiver.

A child restraint includes a seat bottom and a seat back. The seat back includes a backrest and an adjustable headrest that is mounted for up-and-down movement on the backrest by a caregiver.

A child restraint includes a seat bottom and a seat back. The seat back includes a backrest and an adjustable headrest that is mounted for up-and-down movement on the backrest by a caregiver.

A child restraint includes a seat bottom and a seat back. The seat back includes a backrest and an adjustable headrest that is mounted for up-and-down movement on the backrest by a caregiver.